Milk

• Put a drop of milk on polished slanting surface
• Pure milk either stays or flows slowly, leaving a white trail behind
• Milk adulterated with water will flow immediately without leaving a mark

• Take equal parts of milk and water. Shake thoroughly
• If adulterated, dense lather will form
• Pure milk will form a thin layer of foam

Ghee/Butter/Oil

• Take half teaspoon of ghee/butter, add 2-3 drops of tincture of iodine
• Blue colour indicates starch adulteration

• Place oil in refrigerator (not freezer) for 30 minutes
• Coconut oil will solidify

Vegetables

• Rub the outer surface of a small part of the green vegetable with cotton soaked in water or oil
• If the cotton turns green, then it is adulterated

• Place a few green peas in a glass of water
• Let them stand for half an hour
• Clear separation of colour in water indicates adulteration

Spices

• Add a teaspoon of the powdered spice to a glass of water and examine the residue
• A gritty residue indicates presence of brick powder or sand
• If residue is smooth but soapy, soap stone is present
• If sawdust is present, it will float

• Burn a small quantity of asafoetida in a stainless steel spoon
• The pure spice will burn with a bright flame like camphor

• Place a few corns of black pepper in water. Papaya seeds will float

Tea/Coffee

• Spread few tea leaves on a filter paper
• Sprinkle with water to wet the filter paper
• Wash the filter paper under tap water and observe the stains against light
• Pure tea leaves will not stain the filter paper
• If coal tar is present, it will immediately stain the filter paper

• To a glass of water add a teaspoon of coffee powder
• Coffee powder will float while chicory will sink

Wheat Flour

• When dough is prepared from pure flour, less water is needed
• Chapatis will taste somewhat sweetish. Those prepared from adulterated flour are tasteless

Salt

• Stir a spoonful of salt in a glass of water
• If chalk is present, the water will turn white. Other insoluble impurities will settle down